BANGALORE, India, Dec. 7 - Microsoft will invest $1.7 billion in India over the next four years and nearly double its employee ranks in the nation, its chairman, Bill Gates, said Wednesday.

Mr. Gates's announcement was the third in a recent spate of $1 billion investments proposed by technology multinationals in India.

About half of Microsoft's investment is to go toward expanding its existing research and development center, enlarging its global software delivery center and opening retail outlets in 33 Indian cities.

"We have about 4,000 people; we would be growing that by over 3,000 in the next several years," Mr. Gates said in New Delhi at the start of a four-day visit to India.

Western technology corporations have been aggressive in investing in India to tap its pool of technically skilled English-speaking workers, who earn about a fifth of the pay of comparable American workers.

Earlier this week, Intel, the world's largest chip maker, announced that it would invest over $1 billion in India, mostly in research and development, and about $250 million in venture capital investments in Indian technology companies. In October, Cisco Systems, the networking equipment maker, said it would invest $1.1 billion and triple its Indian work force in three years.

Following Intel's example, Mr. Gates said Microsoft would also make venture capital investments in technology start-ups in the country.

Microsoft sends a variety of work to India, from call-center services offering technical support to advanced embedded software development. Its development center in the southern city of Hyderabad is its second-largest campus after its headquarters in Redmond, Wash.

India, increasingly a research and development center for global corporations, is also a rapidly expanding market for technology products. Mr. Gates said Microsoft would focus on developing products for the Indian market, including products tailored to low-cost computing.

The high cost of computers still puts products like those of Microsoft and Intel out of reach for most of India's one billion people. Microsoft nonetheless offers its operating software in several Indian languages.